This relates generally to the field of wireless communications.
In most wireless communication systems, the air link consists of the propagation channel between one transmit antenna and one receive antenna. However, it has been established that using multiple antennas at the transmitter and receiver can significantly increase the link budget and, consequently, link capacity. The drawback of this approach is that the complexity of the system can also increase dramatically.
The increase in link budget or link capacity is achieved via various approaches, including increasing diversity, multiplexing, and beamforming. Beamforming generally involves a training phase in which the receiver learns information about how signals will ultimately be transmitted between the receiver and the transmitter. That information can be provided to the transmitter to appropriately form the beams for the particular communication environment that exists. The communication environment may include interfering stations, obstructions, and any other relevant criteria.